Standardized radio system modeling has been used extensively for determining the performance of wireless units, such as vehicular phones, cell phones, laptops, and wireless tablets. Standardized radio system testing provides for comparison of different models of wireless devices and can be useful during development of wireless devices when the standardized system model sufficiently models the real world environment. As systems have become more sophisticated, so have the standardized radio system models. Today there are well defined radio system models that use two dimensional modeling, wherein a wireless device under test is placed at a test position within an anechoic chamber that has a plurality of probe antennas placed at regular intervals at 90 degrees elevation and 360 degrees azimuth with reference to a normal position of the wireless device under test. (Note that for this document an elevation angle of zero is along an upper half of an axis that is vertical with reference to the horizontal plane.) With the increasing use of multiple-input-multiple-output antennas within devices, more complex mathematical algorithms are proposed to model the radio systems using radio propagation channels in three dimensional models. This results in greater numbers of antenna probes within anechoic test chambers that have been proposed to improve the modeling of the real world environment. The greater number of antenna probes includes probe antennas that are placed anywhere within the full elevation range of 0 to 180 degrees, that are not used in two dimensional models, and at smaller azimuth angular intervals One result of more antenna probes is the need for a larger anechoic chamber to reduce antenna coupling to limits. The increased size and complexity of the test setups can cost substantially more per unit test to run than earlier test systems.
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